Victor Faur, 26, from the western town of Arad, was also accused of breaking into the computers of the US navy and the Department of Energy between November 2005 and September 2006, a statement said.

Romanian police alerted NASA in July last year that its servers had been breached by unknown people based in Romania.

An ensuing probe, launched jointly by Romanian police and the FBI, led to Faur.

NASA had to rebuild its systems and scientists and engineers had to manually communicate with spacecraft, resulting in huge losses for NASA.

Faur, meanwhile, said in television interviews that his action was aimed at "proving that several computers are vulnerable to attack," and underlined that he had not tried to make any "material gains."

"I had neither modified nor erased the files, nor destroyed the communications systems," said Faur, who was formally put under investigation in December and has been barred from leaving the country.

An earlier indictment by the US Attorney's Office charges Faur with leading a hacking group called the "WhiteHat Team," which broke into the systems because of their reputation of being among the most secure in the world.

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